Running a VP9 encode on a linux guest while running a H264 encode on a windows guest causes windows encode hang

Firstly, on Windows 11 using ffmpeg 6.0, `ffmpeg -i Downloads/FPS_test_1080p60_L4.2.mkv -c:v vp9_qsv -f null test` just hangs. So for whatever reason a Windows guest cannot use VP9 encoding.

Secondly, when a Windows 11 guest is running a h264/h265 encode (Eg. `ffmpeg -i Downloads/FPS_test_1080p60_L4.2.mkv -c:v h264_qsv -f null test`) and a linux guest (sharing the same partitioned iGPU) starts a VP9 encode, the Window's encode locks up. Stopping the linux encode allows the windows encode to proceed as expected.

I haven't tried a linux-linux scenario.

Isn't this bad behavior? It seems like a linux guest is able to deny access to the quicksync encoder for any other Windows guest.